Role of metal nanoparticles on porosification of silicon by metal induced etching (MIE)

• Published in: Superlattices and microstructures Vol. 94; pp. 101 - 107
• Main Authors: Saxena, Shailendra K., Yogi, Priyanka, Yadav, Pooja, Mishra, Suryakant, Pandey, Haardik, Rai, Hari Mohan, Kumar, Vivek, Sagdeo, Pankaj R., Kumar, Rajesh
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2016
• Subjects: Metal assisted chemical etching; Metal induced etching; Porous silicon; Silicon nanostructures; Metal assisted chemical etching; Silicon nanostructures; Metal induced etching; Porous silicon
• ISSN: 0749-6036; 1096-3677
• DOI: 10.1016/j.spmi.2016.04.004

Porosification of silicon (Si) by metal induced etching (MIE) process has been studied here to understand the etching mechanism. The etching mechanism has been discussed on the basis of electron transfer from Si to metal ion (Ag+) and metal to H2O2. Role of silver nanoparticles (AgNPs) in the etching process has been investigated by studying the effect of AgNPs coverage on surface porosity. A quantitative analysis of SEM images, done using Image J, shows a direct correlation between AgNPs coverage and surface porosity after the porosification. Density of Si nanowires (NWs) also varies as a function of AgNPs fractional coverage which reasserts the fact that AgNPs governs the porosification process during MIE. The Raman and PL spectrum show the presence of Si NSs in the samples. Depiction of porosification of silicon surface using metal induced etching. [Display omitted] •Mechanism of MIE is discussed in terms of electron transfer and hole injection.•The control of porosity can be achieved in means of control of AgNPs coating.•Direct correlation between surface coverage by AgNPs and surface porosity is observed.